Binary package “courier-maildrop” in ubuntu oneiric

Courier mail server - mail delivery agent

The Courier mail transfer agent (MTA) is an integrated mail/groupware
server based on open commodity protocols, such as ESMTP, IMAP, POP3, LDAP,
SSL, and HTTP. Courier provides ESMTP, IMAP, POP3, webmail, and mailing list
services within a single, consistent, framework.
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The maildrop program is a local mail delivery agent.
it reads a mail message from standard input, then delivers the
message to the mailbox. It is able to deliver mail to
mbox-style mailboxes and Maildirs.
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It will optionally read instructions from a file, which describes how
to filter incoming mail, using a structured filtering language.
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This package is intended for use along with sqwebmail. Otherwise,
use the standalone maildrop package.